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Commands using wc from sorted by
Terminal - Commands using wc - 152 results
$ right(){ l="$(cat -)"; s=$(echo -e "$l"| wc -L); echo "$l" | while read l;do j=$(((s-${#l})));echo "$(while ((j-->0)); do printf " ";done;)$l";done;}; ls --color=none / | right
center(){ l="$(cat -)"; s=$(echo -e "$l"| wc -L); echo "$l" | while read l;do j=$(((s-${#l})/2));echo "$(while ((--j>0)); do printf " ";done;)$l";done;}; ls --color=none / | center
2011-02-14 16:50:35
User: glaudiston
Functions: echo ls read wc
0

Center the output text in max line length of buffered output pipe;

folder=0;mkdir $folder; while find -maxdepth 1 -type f -exec mv "{}" $folder \; -quit ; do if [ $( ls $folder | wc -l ) -ge 100 ]; then folder=$(( $folder + 1 )); mkdir $folder; fi ; done
2011-02-11 21:28:01
User: Juluan
Functions: find ls mkdir mv wc
-1

If you have a folder with thousand of files and want to have many folder with only 100 file per folder, run this.

It will create 0/,1/ etc and put 100 file inside each one.

But find will return true even if it don't find anything ...

find . -type d -name "*TestDir*" | wc -l
2011-01-24 22:38:27
User: linuxgeek
Functions: find wc
-2

A simple command to find the total number of subdirectories in current directory starting with specific name.

nmap -v -sP 192.168.10.0/24 | grep down | wc -l
function where(){ COUNT=0; while [ `where_arg $1~$COUNT | wc -w` == 0 ]; do let COUNT=COUNT+1; done; echo "$1 is ahead of "; where_arg $1~$COUNT; echo "by $COUNT commits";};function where_arg(){ git log $@ --decorate -1 | head -n1 | cut -d ' ' -f3- ;}
2010-12-08 15:41:39
User: noisy
Functions: cut echo head wc
Tags: git
0

usage:

where COMMIT

for instance:

where 1178c5950d321a8c5cd8294cd67535157e296554

where HEAD~5

ls /var/log/ |wc -l
detex document.tex|wc -w
ps -u $USER -lf | grep -vE "\-bash|sshd|ps|grep|PPID" > .tmpkill; if (( $(cat .tmpkill | wc -l) > 0 )); then echo "# KILL EM ALL"; cat .tmpkill; cat .tmpkill | awk '{print $4}' | xargs kill -9; else echo "# NOTHING TO KILL"; fi; cat .tmpkill; rm .tmpkill;
2010-11-04 04:16:50
User: zsugiart
Functions: awk cat echo grep kill ps rm wc xargs
0

Kills all process that belongs to the user that runs it - excluding bash, sshd (so putty/ssh session will be spared). The bit that says grep -vE "..." can be extended to include ps line patterns that you want to spare.

If no process can be found on the hitlist, it will print # NOTHING TO KILL. Otherwise, it will print # KILL EM ALL, with the cull list.

ls |tee >(grep xxx |wc >xxx.count) >(grep yyy |wc >yyy.count) |grep zzz |wc >zzz.count
echo $(echo 'scale=2; ' '100 * ' $(eix --only-names -I | wc -l) / $(eix --only-names | wc -l) | bc -l)%
atb() { l=$(tar tf $1); if [ $(echo "$l" | wc -l) -eq $(echo "$l" | grep $(echo "$l" | head -n1) | wc -l) ]; then tar xf $1; else mkdir ${1%.tar.gz} && tar xf $1 -C ${1%.tar.gz}; fi ;}
2010-10-16 05:50:32
User: elfreak
Functions: echo grep head mkdir tar wc
10

This Anti-TarBomb function makes it easy to unpack a .tar.gz without worrying about the possibility that it will "explode" in your current directory. I've usually always created a temporary folder in which I extracted the tarball first, but I got tired of having to reorganize the files afterwards. Just add this function to your .zshrc / .bashrc and use it like this;

atb arch1.tar.gz

and it will create a folder for the extracted files, if they aren't already in a single folder.

This only works for .tar.gz, but it's very easy to edit the function to suit your needs, if you want to extract .tgz, .tar.bz2 or just .tar.

More info about tarbombs at http://www.linfo.org/tarbomb.html

Tested in zsh and bash.

UPDATE: This function works for .tar.gz, .tar.bz2, .tgz, .tbz and .tar in zsh (not working in bash):

atb() { l=$(tar tf $1); if [ $(echo "$l" | wc -l) -eq $(echo "$l" | grep $(echo "$l" | head -n1) | wc -l) ]; then tar xf $1; else mkdir ${1%.t(ar.gz||ar.bz2||gz||bz||ar)} && tar xf $1 -C ${1%.t(ar.gz||ar.bz2||gz||bz||ar)}; fi ;}

UPDATE2: From the comments; bepaald came with a variant that works for .tar.gz, .tar.bz2, .tgz, .tbz and .tar in bash:

atb() {shopt -s extglob ; l=$(tar tf $1); if [ $(echo "$l" | wc -l) -eq $(echo "$l" | grep $(echo "$l" | head -n1) | wc -l) ]; then tar xf $1; else mkdir ${1%.t@(ar.gz|ar.bz2|gz|bz|ar)} && tar xf $1 -C ${1%.t@(ar.gz|ar.bz2|gz|bz|ar)}; fi ; shopt -u extglob}
wc -l file.txt
ps -a |grep cat |wc -l
fname=$1;f=$(ls -la $fname);fsz=$(echo $f|awk '{ print $5 }');nrrec=$(wc -l $fname|awk '{ print $1 }');recsz=$(expr $fsz / $nrrec);echo "$recsz"
2010-09-14 08:40:22
User: vuurst
Functions: awk echo expr ls wc
0

command was too long...

this is the complete command:

fname=$1; f=$( ls -la $fname ); if [ -n "$f" ]; then fsz=$( echo $f | awk '{ print $5 }' ); if [ "$fsz" -ne "0" ]; then nrrec=$( wc -l $fname | awk '{ print $1 }' ); recsz=$( expr $fsz / $nrrec ); echo "$recsz"; else echo "0"; fi else echo "file $fname does not exist" >&2; fi

First the input is stored in var $fname

The file is checked for existance using "ls -lart".

If the output of "ls -lart" is empty, the error message is given on stderr

Otherwise the filelength is taken from the output of "ls -lart" (5th field)

With "wc -l" the number of records (or lines) is taken.

The record size is filelength devided by the number of records.

please note: this method does not take into account any headers, variable length records and only works on ascii files where the records are sperated by 0x0A (or 0x0A/0x0D on MS-DOS/Windows).

marbles () { c=''; for i in $(seq $1); do c+='{b,r}'; done; x=$(eval echo $c); p=''; for i in $(seq $2); do p+='b*r'; done; y=$(grep -wo "${p}b*" <<< $x); wc -l <<< "$y"; grep -vc 'rr' <<< "$y"; }
2010-08-27 23:04:33
User: quintic
Functions: echo eval grep seq wc
-4

Suppose you have 11 marbles, 4 of which are red, the rest being blue. The marbles are indistinguishable, apart from colour. How many different ways are there to arrange the marbles in a line? And how many ways are there to arrange them so that no two red marbles are adjacent?

There are simple mathematical solutions to these questions, but it's also possible to generate and count all possibilities directly on the command line, using little more than brace expansion, grep and wc!

The answer to the question posed above is that there are 330 ways of arranging the marbles in a line, 70 of which have no two red marbles adjacent. See the sample output.

To follow the call to marbles 11 4: after c=''; for i in $(seq $1); do c+='{b,r}'; done;, $c equals {b,r}{b,r}{b,r}{b,r}{b,r}{b,r}{b,r}{b,r}{b,r}{b,r}{b,r}

After x=$(eval echo $c), and brace expansion, $x equals bbbbbbbbbbb bbbbbbbbbbr ... rrrrrrrrrrb rrrrrrrrrrr, which is all 2^11 = 2048 strings of 11 b's and r's.

After p=''; for i in $(seq $2); do p+='b*r'; done;, $p equals b*rb*rb*rb*r

Next, after y=$(grep -wo "${p}b*"

Finally, grep -vc 'rr'

man $(ls /bin | sed -n $((RANDOM % $(ls /bin | wc -l) + 1))p)
2010-08-20 17:15:33
User: putnamhill
Functions: ls man sed wc
Tags: man sed ls wc random
-2

Great idea camocrazed. Another twist would be to display a different man page based on the day of the year. The following will continuously cycle through all man pages:

man $(ls /bin | sed -n $(($(date +%j) % $(ls /bin | wc -l)))p)
echo "<your twit>" | wc -c -
top -b -n 1 |grep httpd|wc -l
2010-07-25 08:40:03
User: dotanmazor
Functions: grep top wc
-4

Of course, the httpd can be replaced with any other process name

for i in {a..z} ; do man -k $i |grep -i "^$i" |wc | awk 'BEGIN { OFS = ":"; ORS = "" }{print $1, "\t"}' && echo $i ;done
find ~ -maxdepth 20 -type f -size -16M -print > t; for ((i=$(wc -l < t); i>0; i--)) do a=$(sed -n ${i}p < t); mv "$a" /dev/shm/d; mv /dev/shm/d "$a"; echo $i; done; echo DONE; rm t
2010-07-07 04:29:22
User: LinuxMan
Functions: echo find mv rm sed wc
2

Thanks to flatcap for optimizing this command.

This command takes advantage of the ext4 filesystem's resistance to fragmentation.

By using this command, files that were previously fragmented will be copied / deleted / pasted essentially giving the filesystem another chance at saving the file contiguously. ( unlike FAT / NTFS, the *nix filesystem always try to save a file without fragmenting it )

My command only effects the home directory and only those files with your R/W (read / write ) permissions.

There are two issues with this command:

1. it really won't help, it works, but linux doesn't suffer much (if any ) fragmentation and even fragmented files have fast I/O

2. it doesn't discriminate between fragmented and non-fragmented files, so a large ~/ directory with no fragments will take almost as long as an equally sized fragmented ~/ directory

The benefits i managed to work into the command:

1. it only defragments files under 16mb, because a large file with fragments isn't as noticeable as a small file that's fragmented, and copy/ delete/ paste of large files would take too long

2. it gives a nice countdown in the terminal so you know how far how much progress is being made and just like other defragmenters you can stop at any time ( use ctrl+c )

3. fast! i can defrag my ~/ directory in 11 seconds thanks to the ramdrive powering the command's temporary storage

bottom line:

1. its only an experiment, safe ( i've used it several times for testing ), but probably not very effective ( unless you somehow have a fragmentation problem on linux ). might be a placebo for recent windows converts looking for a defrag utility on linux and won't accept no for an answer

2. it's my first commandlinefu command

find -name "*.<suffix>" -exec wc -l "{}" \; | sort -n | tail
2010-06-29 05:53:43
User: cooper
Functions: find sort wc
Tags: wc source java line
0

Find the source file which contains most number of lines in your workspace

:)

countbraces () { COUNT_OPENING=$(echo $1 | grep -o "(" | wc -l); COUNT_CLOSING=$(echo $1 | grep -o ")" | wc -l); echo Opening: $COUNT_OPENING; echo Closing: $COUNT_CLOSING; }
2010-06-23 12:24:18
User: hons
Functions: echo grep wc
1

This function counts the opening and closing braces in a string. This is useful if you have eg long boolean expressions with many braces and you simply want to check if you didn't forget to close one.

history | awk '{a[$'$(echo "1 2 $HISTTIMEFORMAT" | wc -w)']++}END{for(i in a){print a[i] " " i}}' | sort -rn | head
find * -type f -not -name ".*" | xargs wc -l
2010-05-21 21:03:31
User: Leechael
Functions: find wc xargs
1

We use `-not -name ".*"` for the reason we must omit hidden files (which unnecessary). We can only show up total lines like this:

find * -type f -not -name ".*" | xargs wc -l | tail -1